Airplane construction



Dec. 8, 1931 G. M. BELLANCA AIRPLANE CONSTRUCTION Filed Nov. 27, 1928 4Sheets-Sheet 1 Qvwemtoz Dec. 8, 1931. BELLANC'A 1,835,369

AIRPLANE CONSTRUCTION F'il-ed Nov. 27, 1928 \Sheets-Sheet 2 Dec. 8,1931. v BELLANCA 1,835,369 I AIRPLANE CONSTRUCTION Filed Nov. 27, 1928 4Sheets-Sheet I5 Dec. 8, 1931. M BELLANCA 1,835,369

AIRPLANE CONSTRUCTION %ZOM%@W7- Patented men. 8,, tear GUISJEIPPE M.JEELLANCA, F WINGTON, DELAWA.RE

Application filed. November 27, 1928. Serial No. 322,126.

This invention relates to airplane construction and will be understoodfrom the following description read in 0011 unction with the drawings,in which Fig. 1 is a front view of an airplane constructed in accordancewith my invention;

Fig. 2 is an alternative form of construction' 1 Fig. 3 is a detailedperspective side view of Fig. 1 with the outer covering of the wingsremoved;

"Fig. 4 is a side view of Fig. 1;

Fig. 5 is a vertical section through part of Fig. I longitudinal to awing;

Fig; v6 is a section through part of Fig. 1 transverse to a wing;

Fig. 7. 's a top view showing a pin fitting adapted to connect the wingsections; and

Fig. 8 is a horizontal section through part of Fig. 1. Referringspecifically to Figs. 1 and 2, the construction which characterizes myinvention may be applied to either a' double bay job, as illustrated inFig. 1, or to a-job containing three or more bays, as illustrated inFig. 2. The phrase bay as herein employed denotes the space verticallybounded by upper and lower wings and horizontally by two verticalstruts, or a vertical st'rut and some other part of the plane, such asthe fuselage or a strut-wing. In either event the lower wings arerelatively shorter and I provide true wing portions extending diagonallyoutward and upward from the extremities ofthe lower wings to the'upperwlngs, which portions are so formed as to simultaneously function aswings and brace members. These portions'may meet the upper wings at anypoint, such as, for example, the tips, or preferably meet the upperwmgsat points intermediate between the fuselage and tip, thereby placingthat part of the upper wing extending outwardly beyond the polnt ofconnection 1n cantilever and 1mparting a maximum of strength 1n propor.tion to weight. The wing portion so provided having the-combinedproperties of a wing and a strut may'be hereinafter briefly referred toas a strut-wing.-

This strut-wing has at its inner extremity a chord equal to that of thelower wing and preferably tapers with gradually diminishing chord as theupper wing is approached. The lower wing preferably has a chordsubstantially equal to the chord of the upper wing. In the preferredfogm of myinvention the lower wing is relatively short, preferably notexceeding one-third of the length of the upper wing and has a cathedral,that is, it extends, outwardly and downwardly 6 from the fuselage. Sucha wing may be hereinafter referred to as'a stub wing. This stub wing maybe constructed as a true cantilever structure so that vertical or nearlyvertical struts connected adjacent the outer extremity of the lower wingand, extending vertically or nearly so to meet the upper wing may beeliminated. I

It will be apparent that thestrut-wing may be constructed in accordancewith acceptedflo practice to carry stresses incidental to its functionas a lifting member and must, in addition, be adapted to carry tensileand compressive stresses incidental to its function as a strut. Thestrut-wing may comprise 7 only one longitudinal brace or strut sur-'rounded by compression ribs, to which brace the compression ribs areattached. Preferably, however, the struts are in tandem, and Iaccomplish my purpose as illustrated in 9 Fig. 3 by extending theforward and rearward beams 1 and 2 of the strut-wings 3 and carrying thesaid beams upwardly to join the forward and rearward beams a and 5 whichare a part of the'corresponding upper 35 wing. The forward 'andrea'rward beams 1 and 2 in the strut-wing structure operate as struts orbraces to preserve the spatial rela tionship between the upper and lowerwings.-

The strut-wing is provided with the conventional compression ribs 6 orany alterna-, tive means for imparting the necessary backin' to theairfoil. These compression ribsar shown in perspective in Fig. 3. I may,of course, use only one strut extending from the stub wings to the upperwings and utilize this tocarry theribs which back the air foil,

thereby making a true wing portion foundationed on the singlestrutmentioned, or I may employ more than the two struts i1lus trated inFig. 3 as the foundation for a wing portion of this character.Alternatively may employ two or more struts extending from each stubwing to the correspondlng upper wing each of which struts carries aseparate set of ribs and is the foundation of a distinct true wingportion. Such modifications shall be included in the meaning of the termstrut-wing. as herein employed.

As shown diagrammatically in Fig: 6, the forward and rearward beams 1and 2 may be riveted securely to the forward and rearforegoingdescription'of a specific embodi pin-fitting appears in Fig. 7. As amatter of convenience, in the specific type of airplane shown in Fig. 1the upper wings are composed of two sections which are also con: nectedtogether by pin-fittings 10. The relative position of these pin-fittingsand of the forward and rearward beams 1 and 2 is shown in Fig. 8.

It will, of course, be understood that the ment of my invention is byway of illustration and not of limitation. It is my intention that theinvention be limited only by the appended claims, or their equivalents,in

which I have endeavored to claim broadly all inherent novelty.

I claim:

1., An airplane comprisinga fuselage, upper wings extending directlyfrom the sides of said fuselage, relatively shorter lower wings with achord substantially equal to the chord of the upper wings extendingdirectly from the sides of said fuselage, strutwings extending outwardlyand upwardly directly from the sides of said fuselage, strutwinextending outwardly and upwardly from the outer ends of said lower wingsand connected to the said upper wings.

4. An airplane comprising a fuselage, upper wings extending directlyfrom the sides of said fuselage, relatively' shorter lower wingsextending outwardly and downwardly directly from the sides of saidfuselage, strutwings extending outwardly and upwardly from the outerends of said lower Wings and connected to the said upper wings, whichsaid upper wings extend in part outwardly beyond the point of connectionof said strutwings thereto.

,5. An airplane comprising a fuselage,

upper wingsextending directly from the sides of said fuselage,relatively shorter lower wings extending outwardly and downwardlydirectly from the sides of said fuselage with a chord substantiallyequal to the chord of the upper wings, strut-wings extending outwardlyand upwardly from the outer ends of said lower wings and connected tothe said upper 6. Anairplane comprising a fuselage, upper wingsextending directly from the sides of said fuselage, relatively shorter.lower wings'extending outwardly and downwardly directly from the sidesof saidfuselage with.

a chord substantially equal to the chord of theupper wings, strut-wingsextending outwardly and upwardly from the outer ends of said lower wingsand connected to the said upper wings, which said upper wings extendinpartoutwardly beyond the point of connection of said strut-wingsthereto.

In testimony whereof, I have signed my name to this specification this15 day of November, 1928.

- GUISEPPE M. BELLANCA.

from the outer ends of said lower wings and connected to the said upperwings.

2. An airplane comprising a fuselage, up-

per wings extending directly from the sides of sald fuselage, relativelyshorter lower wings with a chord substantiallyequal to the chord of theupper wings extending directly from the sides of said fuselage,strut-wings extending outwardly and upwardly from the outer ends ofsaidlower wings and connected to the said upperwings, which said upperwings extend in'part outwardly beyond the points of connection of saidstrut-wings thereto.

3. An airplane comprising a fuselage, up-

per wings extending directly from the sides of said fuselage, relativelyshorter lower wings extending outwardly and downwardly

